For representing a day of the week.
Capitalized full day names rather than all-caps 3-letter abbreviations
These use the same mapping as Unix.tm_wday
: 0 <-> Sun, ... 6 <-> Sat
As per ISO 8601, Mon->1, Tue->2, ... Sun->7
Mon; Tue; Wed; Thu; Fri
Mon; Tue; Wed; Thu; Fri
Sat; Sun